Food waste is a significant problem worldwide. These food wastes, often discarded without any preliminary processing, can be rich in bioactive substances. In this study, the aim was to identify the phenolic compounds in pumpkin, rosehip and pomegranate seeds, which are frequently consumed in winter. For this purpose, ultrasonically assisted methanolic extracts were prepared from seeds separated from other waste parts (such as shells, stems, and leaves). The results indicated that pomegranate seeds had the highest total phenolic content, with 45.6±3.1 mg GAE/g sample (P<0.05). Similarly, pomegranate seeds also showed the highest total antioxidant capacity in both CUPRAC (114.7±2.6 mg torolox/g sample) and DPPH (71.2±3.8 mg torolox/g sample) analyses (P<0.05). In phenolic profiling analysis using HPLC-PDA, syringic acid was the most abundant compound in pumpkin seeds, (-)-catechin in rosehip seeds, and punicalagin derivatives in pomegranate seeds.

This study investigates the reactions of four summer pumpkin cultivars (cvs. Çağlayan, Mert Bey, Sena Hanım, TG38) to root and crown rot caused by Fusarium proliferatum by taking into account criteria such as disease severity, plant growth (number of leaves, height, dry and fresh weight of shoot) and the accumulation of phenolic compounds in the roots. Seeds of each cultivar were inoculated with the pathogen and left to develop for 1 month at 25oC in a controlled climate room. The content of phenolic compounds in ethanolic root extracts was determined using high-performance liquid chromatography (HPLC). Cv. Sena Hanım had the lowest disease severity (4.40%) among the cultivars, followed by cvs. Çağlayan (10.62%) and Mert Bey (11.07%). Plants developed from inoculated seeds of cvs. Çağlayan and Sena Hanım had no decrease in the number of leaves and in length, fresh and dry weight of shoots in comparison to the control (plants from non-inoculated seeds), while cv. Mert Bey demonstrated a decrease at very low rates in shoot fresh and dry weight (2.24% and 0.77%, respectively). The phenolic compound that exhibited the highest increase in root extracts of cv. Sena Hanım compared to the control among the cultivars was p-coumaric acid (6.57-fold). This study demonstrates that p-coumaric acid can play an important role in the resistance of pumpkin to seed infestation by F. proliferatum.

The purpose of this study was to prepare eight sub-fractions from leaves and flowers of Erica arborea L., characterize their phytochemicals constituents and investigate their potential antioxidant, in order to validate the beneficial medicinal properties of this shrub in Algeria folk medicine. Total polyphenols, flavonoids and condensed tannins contents were determined using Folin-Ciocalteu’s, aluminum chloride and vanillin reagents, respectively. The in vitro antioxidant activity was evaluated by using 2,2-diphenyl-l-picrylhydrazyl and reducing power assay. E. arborea L. contains various compounds such as polyphenols, flavonoids, tannins, quinones, anthraquinones, saponins and terpenoids in different sub-fractions. All the tested extracts showed an appreciable total phenolic, flavonoids and condensed tannins contents as well as strong antioxidant capacity. The highest total phenolic and flavonoids content was found in the ethyl acetate extracts ranging from 649.38 to 944.55 mg gallic acid equivalent/g dry extract and 65.31 to 67.15 mg quercetin equivalent/g dry extract, respectively. Whereas, the highest condensed tannins content was found in the crude extract for leaves and aqueous extracts for flowers. The ethyl acetate extract of the flowers and the crude extract of leaves exhibited the better antioxidant activity by DPPH assay (IC50 =17.72 µg/mL) and reducing power assays (IC50 = 2.91 µg/mL), respectively. Our findings indicate that leaves and flowers extracts are rich in natural antioxidant substances and have good qualities in antioxidant properties and may be beneficial against diver’s disorders related to free radicals.

Natural products play an important role in medicine. They have been used extensively in folk medicine to treat various illnesses. In this work, quantitative analysis of phenolic compounds in methanol, acetonitrile and dichloromethane extracts of Rosa canina L. waste seeds were investigated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) LC-MS/MS. Mineral analysis of R. canina seeds was determined by inductively coupled plasma–atomic emission spectrometry (ICP-OES). Fe, Mn, K and Zn were found as chief elements. Quantitative analysis revealed that catechin was the major flavonoid in all extracts. This work offers a viewpoint for recycling the R. canina waste seeds into the economy due to their bioactive content.

Mushrooms contain a variety of secondary metabolites, including various phenolic compounds, which have been shown to act as excellent antioxidants. In this study, the contents of total phenolic, flavonoids and tannins of mushrooms methanolic extracts were evaluated by colorimetric assays to ranges of 277.36±0.66 to 420.86±0.90 mg (GAE)/100g DW; 31.99±0.90 to 90.90±0.07mg (QE)/100g DW and 150.61±0.16 to 220.47±1.01mg (TAE)/100g DW respectively. HPLC-profiles of methanolic extracts indicated that the individual phenolic compounds found to the samples of the species of mushrooms that are Lentinus squarrosulus and Auricularia politrich revealed us that gallic acid, catechin, acid ρ-hydroxybenzoїc, acid ellagique and naringerin were presented to the level of the two species. With respect to organic acids, the results showed that citric acid and fumaric acid was the major organic acid in all the samples of both mushrooms species. The methanolic extracts of the two mushrooms exhibited the high DPPH radical scavenging activities ranging from 34.10±1.12 to 58.95±0.52%. These data indicated that these mushrooms could constitute a potential good source of natural antioxidant for the local population.

Potato (Solanum tuberosum L.) is one of the most significant vegetable crops for humans along with corn, wheat, and rice. In this study, quantitative analysis of phenolic compounds was carried out for 21 promising potato clones and three commercial cultivars. LC–MS/MS was used for the chemical analyses. The TOGU 3/518 clone had the highest level of 4-hydroxybenzoic acid as 138.51 ± 7.35 µg/kg. TOGU 12/29 and TOGU 2/198 clones, on the other hand, had 126.24 ± 2.29 and 125.29 ± 2.74 µg/kg of 4-hydroxybenzoic acid, respectively. Salicylic acid which is a pharmaceutically significant compound was found in TOGU 3/518 clone (125.66 ± 11.51 µg/kg) as a major product. This compound was also found in TOGU 2/198 (111.27 ±1.31 µg/kg) and TOGU 12/29 clones (111.07 ± 3.68 µg/kg) as the third and fourth most abundant. In terms of caffeic acid, TOGU 3/110 clone contained the highest level (42.50 ± 3.73 µg/kg). While TOGU 7/146 clone included the most protocatechuic acid (53.98 ± 1.47 µg/kg), TOGU 3/480 clone consisted of most gentisic acid (30.79 ± 0.51 µg/kg). Quercetin, an important flavonoid found many aromatic and medicinal plants, was highest in TOGU 12/29 clone (6.27 ± 0.15 µg/kg).

Ultraviolet-B (UV-B: 280 to 320 nm) radiations have appeared to be detrimental to plants, due to their damaging effects on proteins, lipids, membranes and DNA. UV-B radiations are a significant regulator of plants’ secondary metabolites. High intensity of ultraviolet radiations may interfere with growth and productivity of crops. But low levels of UV-B radiations give rise to changes in the plants’ secondary metabolites such as phenolic compounds, carotenoids and glucoseinolates. Therefore, low intensity of UV-B radiations may be used to generate plants, enriched with secondary metabolites, having improved reproductive ability, early ripening and tolerance against fungi, bacteria and herbivores.

This study investigates the reactions of four summer pumpkin cultivars (cvs. Çağlayan, Mert Bey, Sena Hanım, TG38) to root and crown rot caused by Fusarium proliferatum by taking into account criteria such as disease severity, plant growth (number of leaves, height, dry and fresh weight of shoot) and the accumulation of phenolic compounds in the roots. Seeds of each cultivar were inoculated with the pathogen and left to develop for 1 month at 25oC in a controlled climate room. The content of phenolic compounds in ethanolic root extracts was determined using high-performance liquid chromatography (HPLC). Cv. Sena Hanım had the lowest disease severity (4.40%) among the cultivars, followed by cvs. Çağlayan (10.62%) and Mert Bey (11.07%). Plants developed from inoculated seeds of cvs. Çağlayan and Sena Hanım had no decrease in the number of leaves and in length, fresh and dry weight of shoots in comparison to the control (plants from non-inoculated seeds), while cv. Mert Bey demonstrated a decrease at very low rates in shoot fresh and dry weight (2.24% and 0.77%, respectively). The phenolic compound that exhibited the highest increase in root extracts of cv. Sena Hanım compared to the control among the cultivars was p-coumaric acid (6.57-fold). This study demonstrates that p-coumaric acid can play an important role in the resistance of pumpkin to seed infestation by F. proliferatum.

Potato (Solanum tuberosum L.) is one of the most significant vegetable crops for humans along with corn, wheat, and rice. In this study, quantitative analysis of phenolic compounds was carried out for 21 promising potato clones and three commercial cultivars. LC–MS/MS was used for the chemical analyses. The TOGU 3/518 clone had the highest level of 4-hydroxybenzoic acid as 138.51 ± 7.35 µg/kg. TOGU 12/29 and TOGU 2/198 clones, on the other hand, had 126.24 ± 2.29 and 125.29 ± 2.74 µg/kg of 4-hydroxybenzoic acid, respectively. Salicylic acid which is a pharmaceutically significant compound was found in TOGU 3/518 clone (125.66 ± 11.51 µg/kg) as a major product. This compound was also found in TOGU 2/198 (111.27 ±1.31 µg/kg) and TOGU 12/29 clones (111.07 ± 3.68 µg/kg) as the third and fourth most abundant. In terms of caffeic acid, TOGU 3/110 clone contained the highest level (42.50 ± 3.73 µg/kg). While TOGU 7/146 clone included the most protocatechuic acid (53.98 ± 1.47 µg/kg), TOGU 3/480 clone consisted of most gentisic acid (30.79 ± 0.51 µg/kg). Quercetin, an important flavonoid found many aromatic and medicinal plants, was highest in TOGU 12/29 clone (6.27 ± 0.15 µg/kg).